The present invention relates to a method for operating an electromechanically operable parking brake for motor vehicles with a driving engine furnished with a mechanical gear box, being substantially composed of an operating element, an electronic control unit, to which are sent wheel rotational speed values from wheel rotational speed sensors, at least one unit for generating a brake application force, and brake devices on at least one axle being lockable by the unit, with the electronic control unit actuating the unit after detection of a starting maneuver of the motor vehicle in the sense of a release operation of the parking brake.
DE 103 24 446 B3 discloses a method for controlling a brake system equipped with an electric parking brake. In the prior art method, a first stretch of time is determined from the beginning of the coupling action until a point of time of response of the clutch, which corresponds to the so-called clutch bite-point. Subsequently, the release time of the electric parking brake is selected to be ahead of the point of time of response of the clutch by a second stretch of time. The prior art method represents an altogether time-responsive control of the parking brake, and its purpose is to allow a more accurate coordination of the deactivation of the electric parking brake with regard to the clutch-engaging operation and, hence, to the starting maneuver of the vehicle. It is, however, taken into consideration only to an insufficient degree that electric parking brakes typically require a relatively long stretch of time to perform a complete release operation. Therefore, it may occur in quick starting maneuvers that the point of time of response of the clutch is already reached and the electric parking brake is not completely released.
In view of the above, an object of the invention is to disclose a method, which reduces the stretch of time for release of the parking brake in order to achieve greater comfort, while maximum safety is maintained in addition.